Explanation
Why Correct: Manabendranath Roy developed the philosophy of Radical Humanism, which emphasized human freedom, rationality, and secular ethics as alternatives to both capitalism and communism.
Distractor Analysis: Subhas Bose led the Indian National Army and advocated armed struggle. Swami Vivekananda promoted Vedanta philosophy and Hindu spirituality. Bipin Chandra Pal was a nationalist leader in the extremist faction of the Indian National Congress.
Takeaway: M.N. Roy's Radical Humanism rejected both religious dogma and Marxist determinism, advocating instead for a human-centered philosophy based on scientific rationality and individual freedom.